Problem: What is $25\%$ of $4$ ?
Explanation: Having $25\%$ of something means that you get $25$ out of every $100$ We can set up a proportion to find out what number is $25\%$ of $4$ $ \dfrac{{\text{percent}}}{100} = \dfrac{{\text{part}}}{{\text{whole}}}$ Which things do we know, and what are we trying to find? We know the ${\text{percent}}$ is $25$ . Is $4$ the ${\text{part}}$ or the ${\text{whole}}$ The $4$ is the ${\text{whole}}$ . We are trying to find the ${\text{part}}$ that makes up $25\%$ of it: $ \dfrac{{25}}{100} = \dfrac{{\text{part}}}{{4}}$ If we divide the denominator of the fraction on the left by $25$ , it will be the same denominator of the fraction on the right. To keep things equal, let's also divide the numerator on the left by $25$ $ \dfrac{{25} \div 25}{100 \div 25} = \dfrac{{\text{part}}}{{4}}$ $ \dfrac{{1}}{4} = \dfrac{{\text{part}}}{{4}}$ $ {1} = {\text{part}}$ So $1$ is $25\%$ of $4$.